Analysis of spatial distribution of precipitation in Iran using GPM satellite precipitation data

The main goal of the current research is to estimate the spatial distribution of rainfall using satellite remote sensing in the geographical area of Iran. To achieve this goal, calibrated rainfall data of level 3 version 6 of GPM satellite with a spatial resolution of 0.1 x 0.1 degrees from January 2001 to December 2019 were used for the geographical area of Iran. The results showed that in terms of monthly spatial distribution, the heterogeneous distribution of precipitation was evident. Among the rainfall zones, the highest amount of rainfall is related to the rainfall zone of the Caspian Sea coast and then the central Zagros highlands in the west of Iran. The lowest amount of precipitation was also estimated in a wide area of Iran in the central and eastern regions. The seasonal distribution also indicates a significant difference in the distribution of precipitation in different seasons of the year, so that the highest amount of precipitation is related to the winter season and the lowest amount is estimated to be in the summer season. The average rainfall in Iran is 259 mm, which varies from 189 to 344 mm in different years. On the other hand, this small amount of rainfall does not have a homogeneous spatial distribution, so that its largest amount is concentrated in the coastal areas of the north and west, and the smallest amount is concentrated in large areas of central and eastern Iran.